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Figures \((a)\) and \((b)\) show the field lines of a positive and negative point charge respectively.
Question: Figures (a) and (b) show the field lines of a positive and negative point charge respectively.Give the sign of the work done by the field in moving a small positive charge from  Q  to  P .
Give the sign of the work done by the field in moving a small positive charge from \(Q\)  to \(P\) .

Answer

In moving a small negative charge from \(\text B\)  to \(\text A\)  work has to be done by the external agency. It is positive.
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